Concerns are mounting about how the cars behave in dense urban environments, particularly in San Francisco, where there are an estimated 82,000 bike trips each day on over 200 miles of cycling lanes.
Photograph: Alamy

Uber has admitted that there is a “problem” with the way autonomous vehicles cross bike lanes, raising serious questions about the safety of cyclists days after the company announced it would openly defy California regulators over self-driving vehicles.

An Uber spokeswoman said on Monday that engineers were working to fix a flaw in the programming that advocates feared could have deadly consequences for cyclists.

Uber began piloting its self-driving vehicles in its home town of San Francisco last week, despite state officials’ declaration that the ride-share company needed special permits to test its technology. On day one, numerous autonomous vehicles – which have a driver in the front seat who can take control – were caught running red lights and committing a range of traffic violations.

The San Francisco Bicycle Coalition has released a warning about Uber’s cars based on staff members’ first-hand experiences in the vehicles. When the car was in “self-driving” mode, the coalition’s executive director, who tested the car two days before the launch, observed it twice making an “unsafe right-hook-style turn through a bike lane”.

That means the car crossed the bike path at the last minute in a manner that posed a direct threat to cyclists. The maneuver also appears to violate state law, which mandates that a right-turning car merge into the bike lane before making the turn to avoid a crash with a cyclist who is continuing forward.

“It’s one of the biggest causes of collisions,” said coalition spokesman Chris Cassidy, noting that the group warned Uber of the problem. Company officials told the coalition that Uber was working on the issue but failed to mention that the self-driving program would begin two days later without permits, he said.

“The fact that they know there’s a dangerous flaw in the technology and persisted in a surprise launch,” he said, “shows a reckless disregard for the safety of people in our streets.”

The fact that they know there’s a dangerous flaw in the technology and persisted … shows reckless disregard for safety

Chris Cassidy, San Francisco Bicycle Coalition

Uber spokeswoman Chelsea Kohler told the Guardian in an email that “engineers are continuing to work on the problem”, and said that the company has instructed drivers to take control when approaching right turns on a street with a bike lane. She did not respond to questions about how the cars, Volvo XC90s, detect cyclists and what kind of training and testing the firm conducted before implementation.

Linda Bailey, executive director of the National Association of City Transportation Officials, which has raised formal objections to partially automated vehicles, said research raises serious alarms about the ability of drivers to properly intervene in semi-autonomous cars.

“It’s very clear that people are not good at paying attention,” she said, adding, “We’re waiting for enough people to die for something to happen. It’s not a great way to make policy.”

Local advocates noted that the Uber cars have been caught doing four out of the top five causes of collisions or injuries in the city – running red lights, going through stop signs, unsafe turns and failing to yield to pedestrians.

“These behaviors we’re seeing,” said Nicole Ferrara, executive director of advocacy group Walk San Francisco, “are some of the most dangerous behaviors in San Francisco that lead to traffic deaths and severe injuries.”

Carlo Ratti, Massachusetts Institute of Technology professor and director of the Senseable City Lab, noted that the only way to expand self-driving technology is to start testing cars in the real world. But he said the programs must be done in cooperation with regulators, especially considering that the vehicles have to make complex ethical and moral decisions.

“It’s important that government has a say into how the car is programmed,” he said.

Imperfect self-driving vehicles could still be significantly safer than traditional cars, said Jeffrey Tumlin, director of Oakland’s department of transportation.

But he also noted that “bike lanes present a unique challenge for driverless technology”, because cyclists are agile and can travel at high speeds. “It can be more difficult to predict their behavior,” he said, explaining that engineers are already struggling to navigate vehicle responses to pedestrians, which tend to be simpler.

Tumlin said the technology could help improve safety in the long run, but added, “I get uncomfortable with private industry doing their experimentation in the public right of way without first collaborating with the public.”